The present invention relates to an element for the frame of a cabinet for an electrical panel.
Generally, cabinets for low-voltage electrical panels are specifically designed and built so as to meet the functional and installation requirements of the components that constitute the panel. It is in fact known that electrical panels use a system of mutually parallel metallic bars, each of which is connected to a corresponding polarity of a power supply system. Inside the cabinet, the bars are electrically connected to the devices used in the panel, for example circuit breakers, and are geometrically coupled to appropriate insulation and support devices; said insulation and support devices, in addition to mutually electrically insulating the bars, allow to connect them to the structure of the cabinet. In this manner, any electrodynamic stresses produced by the flow of current in the bars are discharged onto the structure of the cabinet, which accordingly must have adequate structural strength characteristics. Furthermore, the electrical devices are arranged on one or more fixing guides, which are connected to the frame of the cabinet either directly or by using additional connecting elements. In order to meet these requirements, cabinets are generally provided with a structure shaped like a parallelepiped, inside which there is an adequate space suitable to accommodate the components of the panel and whose frame allows the anchoring of the elements that support said components, of the cladding panels and of the door of the cabinet.
In particular, the frame comprises two subframes which respectively constitute the lower and upper bases of the parallelepipedal structure; said subframes are typically constituted by four angular elements, generally known as three-way corner joints, which are mutually connected in pairs by virtue of profiled elements arranged substantially in a horizontal position and commonly known as cross-members. In turn, the subframes are mutually connected by using vertical profiled elements, or uprights, each of which connects two corresponding joints. Holes are furthermore provided along the vertical extension of the uprights for the direct fixing of the supporting elements of the electrical devices and of the distribution bars, or for the fixing of intermediate cross-members to which said supporting elements are connected.
In the current state of the art, this solution, despite ensuring an advantageous modular construction, is not entirely satisfactory, particularly as regards the shape and large number of the components required to form the subframes. The connection between the pairs of elements, for example a corner joint and a cross-member, in fact occurs by using a plurality of fixing screws, at least two for each coupling, so as to allow adequate connection and correct mutual positioning of the two elements.
These operations, owing to the number of profiled elements used and therefore to the large number of connections to be provided, require long execution times and a large number of fixing screws; furthermore, in view of the stresses, mainly shear stresses, to which the screws are subjected, said screws may break, consequently entailing a technical drawback.
It is also noted that at least two operators are usually required in order to correctly perform the connections, so that a first operator keeps the elements to be connected in the correct position and the second one actually produces the various connections; accordingly, the assembly and installation costs of the panel increase. Otherwise, i.e., if a single operator works, operations are very time-consuming and difficult to perform.
The aim of the present invention is to provide an element for the frame of a cabinet for an electrical panel which allows to reduce the number of components of said frame, with a consequent benefit from the production standpoint. Within the scope of this aim, an object of the present invention is to provide an element for the frame of a cabinet for an electrical panel which allows to simplify the connection between the various elements of the frame, thus facilitating assembly and reducing production time.
Another object of the present invention is to provide an element for the frame of a cabinet for an electrical panel which is suitable for optimization of the use of the labor required for its production, with a consequent benefit in terms of costs. Another object of the present invention is to provide an element for the frame of a cabinet for an electrical panel which allows to reduce the additional fixing elements to be used, accordingly reducing the number of the corresponding fixing operations.
Another object of the present invention is to provide an element for the frame of a cabinet for an electrical panel in which there is an optimum distribution of the stresses to which the various connections are subjected, so as to avoid any mechanical failures while ensuring high strength of said connections. Another object of the present invention is to provide an element for the frame of a cabinet for an electrical panel which is highly reliable, relatively easy to manufacture and at competitive costs.
This aim, these objects and others which will become apparent hereinafter are achieved by an element for the frame of a cabinet for an electrical panel, characterized in that it comprises:
a first corner joint and a second corner joint which are formed as a monolithic body which has a longitudinal elongated element from the opposite ends of which there protrude a first arm and a second arm, said first and second arms being substantially parallel to each other and perpendicular to the elongated element, and a third arm and a fourth arm for connection to additional components of the frame, said third and fourth arms being arranged substantially parallel to each other and lying substantially at right angles to the elongated element and to the first and second arms;
a first connection element which has an elongated body whose opposite ends are suitable to be connected respectively to the first arm of the first corner joint and to the first arm of the second corner joint;
a second connection element which has an elongated body whose opposite ends are suitable to be connected respectively to the second arm of the first corner joint and to the second arm of the second corner joint; and in that on said first and second corner joints there are coupling means which are suitable to facilitate their connection to said first and second connection elements and to said additional components of the frame.
The element according to the invention therefore allows to reduce, with respect to the known art, the components required to produce the frame; it furthermore comprises components which are configured so as to facilitate the various connections, with significant advantages from the point of view of simplicity, speed and cost of assembly.
Further characteristics and advantages of the invention will become apparent from the description of preferred but not exclusive embodiments of the supporting frame according to the invention, illustrated only by way of non-limitative example in the accompanying drawings, wherein:
FIG. 1 is an exploded perspective view of an element for the frame of a cabinet for an electrical panel according to the invention;
FIG. 2 is a perspective view of a corner joint used in the element according to the invention;
FIG. 3 is a schematic view of a portion of a corner joint with coupling means according to a first embodiment of the invention;
FIG. 4 is a schematic view of a portion of a joint with coupling means according to a second embodiment of the invention;
FIG. 5 is a schematic exploded view of a portion of a joint and of an upright during mutual connection by using coupling means according to another embodiment of the present invention;
FIG. 6 is a view of the element according to the invention during connection to a panel;
FIG. 7 is a view of the element according to the invention during connection to uprights.